The invention relates to body component arrangements for motor vehicles in which the body component has a specific shape, and in which, because of the specific shape, various load and/or stress conditions occur under applied forces in various portions of the body component, in particular high load or stress conditions in a first portion and low load or stress conditions in a second portion.
In the prior art there are known body components that are produced by forming in various ways, usually from metal plates. These variously configured body components, depending on the particular specific component, are provided with a specific shape and a corresponding thickness of material so that they can absorb the forces acting upon them. The thickness of the material of each specific body component may vary in different portions of the component, depending on the applied load and/or stress conditions to be expected. Accordingly, in regions of high load and/or stress conditions, a far greater thickness of material is provided than in regions with lower load and/or stress conditions.
It is known, especially outside the motor vehicle technology, that components, preferably of sheet-like configuration having a different thickness of material in different regions, may be produced by the "tailored blank" technique to produce a reduction of weight. In these component arrangements, different metal elements, generally made of metal sheets and having various structural arrangements and sheet-metal thicknesses, are combined with each other in such a manner that a part of the desired specific shape is formed which has a different wall thickness or thickness of material in correspondingly different regions because of the different metal sheets and different sheet-metal thicknesses used. In addition, parts with differing wall thicknesses may also be produced by costly methods such as pressure casting.
Structural elements to be separately arranged such as disclosed in European Published Application No. 0 633 182 are fabricated in perforated sheets or steel mesh and fastened for example to the inside of vehicle doors or hoods to enhance the mechanical strength or rigidity of a vehicle door. These structural elements are bonded to the corresponding portions of a vehicle door or connected to the sheet metal of the vehicle door by cold forming.
Additional prior art relating to this subject matter is found in German Patents Nos. 574,777 and 692,243.
The prior art methods and the production of the corresponding specific parts, in particular by the "tailored blank" technique, are very expensive, depending on the nature of the specific parts to be produced, since a thin sheet must be thickened locally. Consequently, parts produced in this manner are extremely cost-intensive. Another disadvantage of the prior art is that, while a correspondingly small thickness of material is provided in the region of a lower load and/or stress condition, this reduced thickness of material does not always ensure that the load and/or stress condition occurring in that region will be substantially uniform under the action of an applied force because the load or stress condition is dependent on various factors such as the point of application of a force, the specific shape of the component, the structural arrangement of the metal, etc. A non-uniform load and/or stress condition in a region having a smaller thickness of material may in any event lead, especially over any long period of time under load, to cracks, elongations or even failure of or damage to that region. As a result, not only is the production of such parts very cost-intensive on the one hand, the parts are not always optimal on the other hand.